Image reading apparatus with multi-sheet feed detection

ABSTRACT

An image reading apparatus includes a transport section that can transport original documents along a transport path, a reading section configured to read images of the original documents transported by the transport section, an output controller configured to output data of the original documents read by the reading section, a multi-sheet feed detection sensor configured to detect a multi-sheet feed of the original documents transported by the transport section, and an instruction section configured to issue an instruction to disable multi-sheet feed detection by the multi-sheet feed detection section.

This application is a reissue application of U.S. Pat. No. 10,015,338,which was filed as U.S. patent application Ser. No. 15/334,361 on Oct.26, 2016 and issued on Jul. 3, 2018, which claims priority to JapanesePatent Application No. 2015-213924 filed on Oct. 30, 2015, thedisclosure of which are incorporated herein by reference in itsentirety.

BACKGROUND

1. Technical Field

The present invention relates to an image reading apparatus such as ascanner that reads images of original documents.

2. Related Art

Typical image reading apparatuses separate a plurality of originaldocuments mounted on an original platen (placement section) one by one,transport the original documents, and read images of the originaldocuments (see, for example, JP-A-2012-41118).

Such image reading apparatuses include a multi-sheet feed detectionsensor (multi-sheet feed detection section) for detecting whether aplurality of original documents are transported in an overlapped state(hereinafter, also referred to as a multi-sheet feed). Such imagereading apparatuses have a separation mode for separating the originaldocuments on the original platen and transporting the originaldocuments, and a non-separation mode for manually feeding the originaldocuments. While the non-separation mode is selected, the multi-sheetfeed state detected by the multi-sheet feed detection sensor isdisabled.

In other words, in the image reading apparatuses, original documentssuch as envelopes and center-folded original documents, which aretransported one by one but may be erroneously detected as a multi-sheetfeed, are manually fed one by one in the non-separation mode.

In some cases, however, image reading apparatuses have to read aplurality of original documents including original documents such asenvelopes that tend to be erroneously detected as a multi-sheet feed,even if a single envelope is fed, and original documents that are rarelydetected as an error such as paper. In such a case, it is laborious tofeed the original documents one by one to read the original documents inthe non-separation mode. On the other hand, if the original documentsare read in the separation mode, the multi-sheet feed detection sensormay erroneously detect an error, and the reading operation may bestopped. In such a case, the erroneously detected original documents areto be read in the non-separation mode, and this operation causes theread data to be split into a plurality of files corresponding to beforeand after the detected error.

SUMMARY

An advantage of some aspects of the invention is that there is providedan image reading apparatus capable of reducing the splitting of readdata into a plurality of files when original documents to be readinclude original documents that tend to be erroneously detected as amulti-sheet feed.

Hereinafter, an apparatus for solving the above-mentioned problem andits operational advantages will be described. An image reading apparatusthat can solve the above-mentioned problem includes a transport sectionconfigured to transport original documents along a transport path, areading section configured to read images of the original documentstransported by the transport section, an output controller configured tooutput data of the original documents read by the reading section, amulti-sheet feed detection section configured to detect a multi-sheetfeed of the original documents transported by the transport section, andan instruction section configured to issue an instruction to disablemulti-sheet feed detection by the multi-sheet feed detection section.After a job for sequentially transporting a plurality of originaldocuments to perform a reading operation to read images is interruptedby multi-sheet feed detection performed by the multi-sheet feeddetection section, and if the job is restarted in a disabling mode inwhich the multi-sheet detection is disabled in accordance with aninstruction from the instruction section, the output controller outputs,as a data stream that can be saved as a single file, first data that isread in the reading operation before the interruption and second datathat is read in the reading operation after the restart.

With this structure, the output controller outputs the first data andthe second data as a data stream. Accordingly, the first data readbefore the interruption and the second data read after the restart canbe merged into a single file even if the job is interrupted by themulti-sheet feed detection. Consequently, the splitting of the read datainto a plurality of files can be reduced when the original documents tobe read include original documents that tend to be erroneously detectedas a multi-sheet feed.

It is preferable that the image reading apparatus further include atransport detection section configured to detect the original documentstransported by the transport section. The disabling mode includes anoriginal document unit disabling mode for disabling the multi-sheet feeddetection by the multi-sheet feed detection section until the trailingedges of the original documents pass through the multi-sheet feeddetection section, and if the original document unit disabling mode isinstructed by the instruction section, in response to detection of thepassage of the trailing edges of the original documents through themulti-sheet feed detection section based on a detection signal by thetransport detection section, the multi-sheet feed detection by themulti-sheet feed detection section is enabled.

With this structure, for example, to read the original documents thattend to be erroneously detected as a multi-sheet feed, the originaldocument unit disabling mode can be selected to disable the multi-sheetfeed detection by the multi-sheet feed detection section until theoriginal documents have passed through the multi-sheet feed detectionsection. After the passage of the original documents, the multi-sheetfeed detection can be enabled.

It is preferable that in the image reading apparatus, the disabling modeinclude a job unit disabling mode for disabling the multi-sheet feeddetection by the multi-sheet feed detection section until the job iscomplete. If the job unit disabling mode is instructed by theinstruction section, in response to the job completion, the multi-sheetfeed detection by the multi-sheet feed detection section is enabled.

With this structure, in the job unit disabling mode, the multi-sheetfeed detection can be disabled until the job is complete. Accordingly,the job interruption caused by erroneous detection can be reduced, forexample, when original documents that tend to be erroneously detected asa multi-sheet feed are included in the original documents to be read ina single job. After job completion, the multi-sheet feed detection canbe enabled.

It is preferable that the image reading apparatus further include aplacement section on which the original documents to be read aremounted, a placement detection section configured to detect the originaldocuments mounted on the placement section, and a transport detectionsection configured to detect the original documents mounted on theplacement section and transported by the transport section. From the jobinterruption to the job restart, the disabling mode set in accordancewith the instruction from the instruction section is maintainedregardless of the detection results of the placement detection sectionand the transport detection section.

With this structure, from the job interruption to the job restart, theplacement detection section and the transport detection section detectresetting of the original documents. However, from the job interruptionto the job restart, regardless of the detection results of the placementdetection section and the transport detection section, the disablingmode is maintained, and thereby the job can be restarted in thedisabling mode after resetting the original documents.

It is preferable that in the image reading apparatus, the disabling modeinclude a disable maintaining mode for maintaining the state in whichthe multi-sheet feed detection by the multi-sheet feed detection sectionis disabled until the power supply is switched off. With thisconfiguration, in the disable maintaining mode, in response to a disableinstruction by the instruction section, the multi-sheet feed detectioncan be disabled until the power is switched off. Accordingly, the jobinterruption caused by erroneous detection can be reduced whenperforming a plurality of jobs including original documents that tend tobe erroneously detected as a multi-sheet feed.

It is preferable that, in the image reading apparatus, the instructionsection issue an instruction for starting the job, and the interruptedjob be restarted in accordance with the start instruction from theinstruction section.

With this configuration, the interrupted job can be restarted at anytime by instructing the instruction section to issue an instruction tostart the job.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a perspective view of an image reading apparatus according toan embodiment.

FIG. 2 is a schematic side cross-sectional view of the image readingapparatus.

FIG. 3 is a schematic plan view of a transport surface section of a bodysection.

FIG. 4 is a schematic side view of overlapped original documentsdetected by a multi-sheet feed sensor.

FIG. 5 is a block diagram illustrating an electrical configuration and afunctional configuration of the image reading apparatus.

FIG. 6 is a flowchart illustrating multi-sheet feed detection disablingprocessing.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, an image reading apparatus according to an embodiment willbe described with reference to the attached drawings. As illustrated inFIG. 1 , an image reading apparatus 11 according to the embodimentincludes an apparatus body 12 (hereinafter, simply referred to as “body12”) that has a substantially trapezoidal shape in side view, and anoriginal support 13 that is an example placement section having amounting surface 13A onto which original documents D (see FIG. 2 ) thatare to be read are mounted (set). The original documents D mounted onthe original support 13 are fed one by one to a feed port 12A that isopen to an upper portion of the body 12. The fed original documents Dare transported in the body 12 along a predetermined transport path 32(see FIG. 2 ), and the images of the original documents are read at areading position on the transport path. The original documents are thendischarged from a discharge port 12B that is open to a front lowerportion of the body 12 and stacked, for example, on a discharge tray 18A(see FIG. 2 ).

The original support 13 includes a first support section 14 that isrotatably connected to the body 12 at a base end portion (lower endportion), and a second support section 15 that is rotatably connected toan end portion of the first support section 14 at a base end portion. Aslidable auxiliary support section 16 is provided at an end portion ofthe second support section 15. The original support 13 extends upward inan inclined manner from the rear of the body 12 and can be arranged inan open position (use position) where the original support 13 serves asa support on which the original documents D can be mounted, asillustrated in FIG. 1 , or in a closed position (stored position) wherethe original support 13 can be adjusted by a user to cover an uppersurface portion and a front surface portion 12C of the body 12 byturning the original support 13 from the open position toward the papersurface in FIG. 1 .

A pair of edge guides 17 that can be slid in width directions X whichintersect (specifically, are orthogonal to) a transport direction Y inwhich the original documents D are transported are provided on themounting surface 13A of the original support 13. The original documentsD mounted on the mounting surface 13A are held by the pair of edgeguides 17, and thereby the original documents D are positioned in thewidth direction X with respect to the feed port 12A. Note that the widthdirection X is a main scanning direction along which the image readingapparatus 11 reads images of the original documents D, and the transportdirection Y is a sub-scanning direction.

As illustrated in FIG. 1 and FIG. 2 , the body 12 includes a bodysection 18 and a cover section 19 that is connected to the body section18 such that the cover section 19 can rotate about a front end portionof the body section 18. A transport path 32 from the feed port 12A tothe discharge port 12B is provided between the body section 18 and thecover section 19 as illustrated in FIG. 2 when the cover section 19 isarranged in the closed position illustrated in FIG. 1 and FIG. 2 . Atransport surface section 39 (see FIG. 3 ) that is a surface section ofthe transport path 32 is exposed when a user operates the operationsection 19A illustrated in FIG. 1 to release the engagement of the coversection 19 and rotates the cover section 19 from the closed positionillustrated in FIG. 1 toward the paper surface illustrated in FIG. 1 andto the open position. By opening the cover section 19 and exposing thetransport surface section 39, the user can, for example, remove lodged(jammed) original documents D and perform maintenance of rollers 33A to36A for feeding and transporting original documents (see FIG. 2 ).

An instruction section 20 for issuing an instruction for starting a job,an instruction for disabling multi-sheet feed detection, or the like isprovided on the front surface portion 12C of the body 12 (cover section19), as illustrated in FIG. 1 . The term “multi-sheet feed” refers to astate in which a plurality of original documents D mounted on theoriginal support 13 are transported in an overlapped state. Theinstruction section 20 includes a plurality of switches 21 to 26 forissuing instructions to the image reading apparatus 11. Specifically,the instruction section 20 includes various switches such as a powerswitch 21, a start switch 22, a stop switch 23, a read mode selectionswitch 24, a multi-sheet feed detection disabling switch 25 (multi-sheetfeed detection skip switch), and a wireless communication switch 26.

The power switch 21 is operated by a user to issue an instruction forswitching between starting power supply to the image reading apparatus11 and stopping the power supply. The start switch 22 is used to issuean instruction to start a job for transporting at least one, forexample, a plurality of original documents D mounted on the originalsupport 13 in sequence and performing a reading operation for readingimages. The stop switch 23 is used to issue a stop instruction forinterrupting or stopping the job started by the operation of the startswitch 22. The read mode selection switch 24 is used to issue aninstruction for specifying an image reading mode for reading images in areading operation, for example, a color mode (e.g., monochrome or color)or image quality.

The multi-sheet feed detection disabling switch 25 is operated by a userto issue an instruction for disabling multi-sheet feed detection toswitch to a disabling mode for disabling multi-sheet feed detection fordetecting whether a multi-sheet feed has occurred. The wirelesscommunication switch 26 is used to issue an instruction for switchingwireless communication on and off.

At a position adjoining to the instruction section 20, a notificationsection 27 that includes pilot lamps that can light up and/or blink andgo out, for example, light-emitting diodes (LEDs), or pilot lamps thatcan change colors when lit, is provided. The notification section 27 isused to notify a user of, for example, whether the power supply isturned on or off, a currently selected mode, or whether multi-sheet feeddetection is enabled or disabled by turning on or off the pilot lamps orby changing their colors.

An image reading processing mechanism 30 for image reading processing(scan processing) is provided in the body 12 of the image readingapparatus 11, as illustrated in FIG. 2 . The image reading processingmechanism 30 includes a transport section 31 that transports theoriginal documents D. The transport section 31 guides and transports aplurality of original documents D mounted on the original support 13 oneby one from the feed port 12A along a plate-like feed guide 32A into thebody 12 and transports the fed original documents D along the transportpath 32 at a constant transport speed.

The transport section 31 includes a feeding roller pair 33 that isdisposed at an upstream end position of the transport path 32 in thebody 12, and a feeding roller pair 34 that is disposed downstream of thefeeding roller pair 33 in the transport direction. The transport section31 further includes a transport roller pair 35 that is disposed upstreamof the reading position of the original documents D and a transportroller pair 36 that is disposed downstream of the reading position inthe transport direction Y.

The feeding roller pairs 33 and 34 include driving rollers 33A and 34Aand driven rollers 33B and 34B. The transport roller pairs 35 and 36include driving rollers 35A and 36A and driven rollers 35B and 36B. Thedriven rollers 33B to 36B rotate in response to the rotation ofcorresponding driving rollers 33A to 36A respectively.

The driving rollers 33A to 36A of the roller pairs 33 to 36 are rotatedand driven by the power of a transporting motor 37 that is the powersource of the rollers. The driven rollers 34B of the feeding roller pair34 serve as retard rollers, and the coefficients of friction against theoriginal documents D on their outer circumferential surfaces are largerthan those of the driving rollers 34A. Accordingly, the feeding rollerpair 34 serves as a separation mechanism 38 that separates the originaldocuments D one by one and sends the separated original documents to thedownstream side in the transport direction Y. That is, a plurality oforiginal documents D mounted on the original support 13 are fed, forexample, from the lowest original in sequence one by one from the feedport 12A into the body 12 by the rotation of the feeding roller pair 33and are further separated one by one and fed to the downstream side inthe transport direction Y by the rotation of the feeding roller pair 34.

As illustrated in 2, a reading section 40 that reads images of theoriginal documents D transported by the transport section 31 is providedat the reading position in the middle of the transport path 32 that isdefined by the feeding roller pairs 33 and 34 and the transport rollerpairs 35 and 36 in the body 12. The reading section 40 includes a firstreading section 40A and a second reading section 40B that are disposedon both sides of the transport path 32 at positions slightly shifted inthe transport direction Y such that the sections 40A and 40B do notdirectly face each other. The pair of reading sections 40 includes alight source 41 that can emit light toward the original document D beingtransported and an image sensor 42 that extends in the main scanningdirection (width direction X). In a normal reading mode for reading oneside (front surface) of the original document D, the first readingsection 40A performs a reading operation, and in a two-sided readingmode for reading both sides (front and rear surfaces) of the originaldocument D, the first reading section 40A and the second reading section40B perform a reading operation together.

The light source 41 may be, for example, an LED or a fluorescent lamp.The image sensor 42 receives the light emitted from the light source 41and reflected by the original documents D, or the like, converts thereceived light into electrical signals, and outputs pixel signals ofvalues corresponding to the amounts of received light. The image sensor42 may be, for example, a linear image sensor. The image readingapparatus 11 can perform color scanning and monochrome scanning(gray-scale scanning). The color scanning includes a method in whichlight sources of RGB emit light in a time-series order and pixel signalsof RGB are acquired from a monochrome image sensor in this order, and amethod in which an image sensor that includes photoelectric converterscovered with respective RGB color filters is provided, a white lightsource emits light, and pixel signals of RGB are acquired from thephotoelectric converters. Any one of the color scanning methods may beemployed. In the description below, the light source 41 and the imagesensor 42 may be referred to as components of the first reading section40A, a first light source 41A, and a first image sensor 42A,respectively and as components of the second reading section 40B, asecond light source 41B, and the second image sensor 42B, respectively.

A color reference plate 43 is disposed on the opposite side of thetransport path 32 to the image sensor 42. The color reference plate 43is used to obtain a white reference value for shading correction, and awhite reference plate or gray reference plate is used. The grayreference plate is used to detect the position and area of the originaldocument D from data read by using the color reference plate 43 as abackground (gray background) of the original, based on a differencebetween the colors or luminance values of the original and thebackground. It is preferable that the white reference plate be used asthe color reference plate 43 when detecting an original by using asensor dedicated for original detection.

The image sensor 42 may be, for example, a contact type image sensorthat has a plurality of photoelectric converters aligned in the mainscanning direction (width direction X). More specifically, the imagesensor 42 may be a complementary metal oxide semiconductor (CMOS). Theimage sensor 42 performs photoelectric conversion of the light receivedby each photoelectric converter and outputs pixel signals correspondingto the amounts of received light.

A controller 50 provided in the body 12 controls the transporting motor37, the light source 41 and the image sensor 42 included in the readingsection 40 (40A and 40B). The controller 50 further controls the imagereading apparatus 11 in accordance with instructions given by operationsignals from the instruction section 20 operated by a user.

The transport surface section 39 that is a surface section of a lowerside of the transport path 32 for the original documents D is describedwith reference to FIG. 3 . The transport surface section 39 that isdefined by an upper surface of the body section 18 includes a transportplate 18B that covers the upper surface of the body section 18 and aplurality of ribs 18C that protrude from the upper surface and extend inparallel with each other along the transport direction Y. In asubstantially central portion of the transport surface section 39 in thewidth direction X, the driving rollers 33A and 34A included in thefeeding roller pairs 33 and 34, and the driving rollers 35A and 36Aincluded in the transport roller pairs 35 and 36 are disposedrespectively as pairs with a certain space in the width direction X inthis order from the upstream side in the transport direction Y. Aplacement sensor 45, which is an example placement detection section fordetecting the original documents D mounted on the original support 13,is disposed between the pair of driving rollers 33A included in thefeeding roller pair 33. The placement sensor 45 is, for example, acontact sensor having a lever, and detects whether the originaldocuments D mounted on the original support 13 exist in response to apressing operation of the lever.

A multi-sheet feed sensor 46, which is an example multi-sheet feeddetection section for detecting a multi-sheet feed of the originaldocuments D transported by the transport section 31, is disposed betweenthe feeding roller pair 34 and the transport roller pair 35 in thetransport direction Y, as illustrated in FIG. 3 and FIG. 4 . Themulti-sheet feed sensor 46 is, for example, an ultrasonic sensor, andincludes a transmitter 46A (see FIG. 4 ) that can transmit ultrasoundand a receiver 46B that is disposed on the opposite side of thetransport path 32 from the transmitter 46A and can receive theultrasound from the transmitter 46A. The multi-sheet feed sensor 46detects a multi-sheet feed of the original documents D using theprinciple that ultrasound from the transmitter 46A is attenuated due tospaces between overlapped two original documents. The degree ofattenuation of the ultrasound passed through two or more originaldocuments D is larger than that of the ultrasound passed through oneoriginal document D. Accordingly, if a detected value exceeds (is below)a predetermined threshold value due to the large degree of attenuation,it is determined to be a multi-sheet feed. In contrast, since the degreeof attenuation of the ultrasound passed through one original document Dis small, the detected value does not exceed the predetermined thresholdvalue, and it is not determined to be a multi-sheet feed.

Accordingly, if the original document D that has an overlapped portion,for example, an envelope or folded paper is used, since the degree ofattenuation of the ultrasound due to the spaces in the overlappedportion is large, the multi-sheet feed sensor 46 may erroneouslydetermine the one original document D being transported to be amulti-sheet feed. Accordingly, to read the original document D thattends to be erroneously determined to be a multi-sheet feed, the usercan operate the multi-sheet feed detection disabling switch 25 to issuean instruction for disabling the multi-sheet feed detection by themulti-sheet feed sensor 46 to set a disabling mode that disables themulti-sheet feed detection.

Furthermore, a transport sensor 47, which is an example transportdetection section for detecting the original documents D mounted on theoriginal support 13 and transported by the transport section 31, isdisposed between the pair of driving rollers 35A included in thetransport roller pair 35. The transport sensor 47 is, for example, acontact sensor having a lever (contactor), and detects the leading edgewhen the leading edge of the original document D pushes the lever and anon-detection state (off) is switched to a detection state (on), anddetects the trailing edge when the trailing edge passes through thelever and the lever is not pushed and the detection state is switched tothe non-detection state. The detection result of the transport sensor 47is used to control the time of starting and ending the reading operationof the reading section 40 (40A, and 40B) that is disposed downstream inthe transport direction Y.

With reference to FIG. 5 , an electrical configuration of the imagereading apparatus 11 is described. As illustrated in FIG. 5 , thecontroller 50 includes a computer 51 that has a microprocessor, and thelike, and a storage section 52. The controller 50 further includes aninput section 55 that has an input interface for inputting various kindsof data and signals from a host device 53, and an output section 56 thathas an output interface for outputting data read by the image readingapparatus 11 to the host device 53.

The controller 50 further includes a timing generator (TG) 57 foroutputting pulse signals defining the time of various operationsincluding an operation of reading a pixel signal for the reading section40 (image sensors 42A and 42B). The controller 50 also includes ananalog front end (AFE) 58 that performs analog-to-digital conversion(A/D conversion) of pixel signals input from the image sensors 42A and42B. The storage section 52 includes, for example, a nonvolatile memoryand a random access memory (RAM).

The image reading apparatus 11 is connected to the host device 53 via acommunication cable. The host device 53 may be, for example, a personalcomputer (PC). It should be noted that the host device 53 is not limitedto the PC, and may be a personal digital assistant (PDA), a tablet PC,or a smart device such as a smart phone. The host device 53 includes acreation section 60 that creates a file based on data output from theimage reading apparatus 11.

The storage section 52 in FIG. 5 stores a program (PR) and the like thatincludes a program for multi-sheet feed detection disabling processingillustrated in the flowchart in FIG. 6 . The computer 51 in FIG. 5serves as a functional section of various functions illustrated in FIG.5 by executing the program PR. That is, as illustrated in FIG. 5 , thecomputer 51 includes, as the functional section, a main controller 62, atransport controller 63 for controlling the transporting motor 37, amode controller 64, a reading controller 65 for controlling the readingsection 40, and an output controller 66 for controlling output of dataof the original documents D read by the reading section 40.

The transport controller 63 drives the transporting motor 37 inaccordance with an instruction from the main controller 62 to rotate theroller pairs 33 to 36 such that the original documents D mounted on theoriginal support 13 is fed into the body 12 one by one. The transportcontroller 63 further transports the fed original documents D along thetransport path 32 at a constant transport speed corresponding to theread conditions.

The mode controller 64 switches an enabling mode for enabling themulti-sheet feed detection by the multi-sheet feed sensor 46 and adisabling mode for disabling the multi-sheet feed detection inaccordance with an instruction from the multi-sheet feed detectiondisabling switch 25. The disabling mode according to the embodimentincludes an original document unit disabling mode, a job unit disablingmode, and a disable maintaining mode, which control different timeperiods for maintaining a disabled state, respectively. These disablingmodes are set, for example, depending on an operation of the multi-sheetfeed detection disabling switch 25.

In the original document unit disabling mode, multi-sheet feed detectionby the multi-sheet feed sensor 46 is disabled until the trailing edgesof the original documents D pass through the multi-sheet feed sensor 46.The original document unit disabling mode is set when a user performs afirst operation (for example, presses the multi-sheet feed detectiondisabling switch 25 once) and a first instruction is issued.

In the job unit disabling mode, the multi-sheet feed detection by themulti-sheet feed sensor 46 is disabled until the job ends. The job unitdisabling mode is set when a user performs a second operation (forexample, presses the multi-sheet feed detection disabling switch 25twice) and a second instruction is issued.

In the disable maintaining mode, the multi-sheet feed detection by themulti-sheet feed sensor 46 is disabled until the power supply isswitched off. The disable maintaining mode is set when a user performs athird operation (for example, presses long the multi-sheet feeddisabling switch 25) and a first instruction is issued.

The enabling mode is set when any of the first to third operations isnot performed or a reset operation (for example, the stop switch 23 ispressed once while a reading operation is interrupted) is performed.

The reading controller 65 controls the reading section 40 while theoriginal documents D are being transported to read images of theoriginal documents D. Specifically, the reading controller 65 outputspulse signals to the image sensor 42 via the TG 64 to control readingtime for reading pixel signals and thereby the reading operations arecontrolled. The analog pixel signals output from the reading section 40are converted into digital pixel signals via the AFE 58 and input intothe output controller 66 as read data.

The output controller 66 performs known image correction processing suchas shading correction and gamma correction to the read data containingthe input digital pixel signals to generate image data of the originaldocuments D. Then, the output controller 66 outputs the generated imagedata to the host device 53 via the output section 56.

Hereinafter, the multi-sheet feed detection disabling processing to beexecuted by the computer 51 is described with reference to the flowchartin FIG. 6 . The computer 51 starts a job for performing a readingoperation of the original documents D and performs multi-sheet feeddetection disabling processing in response to an operation of the startswitch 22 while the original documents D are mounted on the originalsupport 13. In this embodiment, a single job includes transporting theoriginal documents D mounted on the original support 13 one by one fromthe first original, causing the reading section 40 to read images, andreading an image on the last original document D.

In step S11, the computer 51 initializes the value of N corresponding tothe pages of the original documents D to one. In step S12, the computer51 performs an operation for reading an Nth original document D.Specifically, the transport controller 63 drives the transporting motor37 to feed and transport the original documents D mounted on theoriginal support 13, and the reading controller 65 instructs the readingsection 40 to read images of the original documents D at the time theoriginal documents D pass through the reading position.

In step S13, the computer 51 determines whether the enabling mode forenabling the multi-sheet feed detection has been set. If the enablingmode has been set (step S13: YES), in step S14, the computer 51determines whether a multi-sheet feed has occurred. For example, whenthe original documents D are envelopes, the multi-sheet feed sensor 46may be turned on while the envelopes are transported one by one, and themulti-sheet feed sensor 46 may erroneously determine that a multi-sheetfeed has occurred (step S14: YES).

In step S15, the computer 51 interrupts the reading operation.Specifically, the transport controller 63 stops the driving of thetransporting motor 37, and the reading controller 65 stops the readingof the images of the original documents D by the reading section 40.Furthermore, in step S16, the computer 51 turns on an interruption flag,and in step S17, outputs first data. Specifically, the output controller66 outputs the image data of the original documents D (Nth to firstoriginal documents) read before the job interruption as the first data.

In step S18, the computer 51 notifies the user of the detection of amulti-sheet feed. In step S19, the computer 51 determines whether thedisabling mode for disabling the multi-sheet feed detection has beenset. While the disabling mode has not been set (step S19: NO), thecomputer 51 stands by until the disabling mode is set. In response to anoperation of the multi-sheet feed detection disabling switch 25 by theuser, the mode controller 64 sets the disabling mode corresponding tothe instruction. If the disabling mode has been set (step S19: YES), instep S20, the computer 51 determines whether a restart instruction hasbeen issued. Specifically, while the start switch 22 is not pressed bythe user (step S20: NO), the computer 51 stands by until the startswitch 22 is pressed. If the start switch 22 is pressed, the computer 51moves to the processing in step S12, and restarts the interruptedreading operation of the Nth original document D.

In step S13, if the disabling mode has been set (step S13: NO), thecomputer 51 moves to the processing in step S21. In step S14, if themulti-sheet feed sensor 46 has not detected a multi-sheet feed (off)(step S14: NO), the computer 51 moves to the processing in step S21.

In step S21, the computer 51 determines whether the transport sensor 47is switched from on to off. That is, the transport sensor 47 is switchedfrom off to on when the leading edge of the original document D istransported to the transport sensor 47. While the original documents Dare passing through the transport sensor 47 (step S21: NO), the computer51 moves the processing to step S12. If the trailing edge of theoriginal document D passes through the transport sensor 47 and thetransport sensor 47 is switched from on to off (step S21: YES), in stepS22, the computer 51 determines whether the original document unitdisabling mode has been set.

If the original document unit disabling mode has been set (step S22:YES), in step S23, the mode controller 64 changes the original documentunit disabling mode to the enabling mode. If the mode that has been setis not the original document unit disabling mode (step S22: NO), in stepS24, while the mode is maintained, the computer 51 determines whetherthe placement sensor 45 is off.

Specifically, if the original documents D are mounted on the originalsupport 13 and the placement sensor 45 is on (step S24: NO), in stepS25, the computer 51 adds one to N, and moves to step S12 to perform thereading operation of the next original document D.

If all of the original documents D that have been mounted on theoriginal support 13 are fed and the placement sensor 45 is off (stepS24: YES), in step S26, the computer 51 determines whether theinterruption flag is on.

If the interruption flag is on (step S26: YES), in step S27, thecomputer 51 outputs the second data. That is, the output controller 66outputs the image data read in the reading operation performed after theinterruption as the second data that can be merged with the first dataoutput in step S17 into a single file as a data stream. In step S28, thecomputer 51 turns off the interruption flag.

In step S26, if the interruption flag is off (step S26: NO), in stepS29, the computer 51 outputs the image data. That is, since the job isnot interrupted, the output controller 66 outputs the image data of alloriginal documents D from the original document read first to theoriginal document read last.

In step S30, the computer 51 determines whether the job unit disablingmode has been set. If the job unit disabling mode has been set (stepS30: YES), in step S31, the mode controller 64 changes the job unitdisabling mode to the enabling mode, and ends the processing. If the jobunit disabling mode has not been set (stop S30: NO), the mode controller64 maintains the settings, and ends the processing.

Now, the operation of reading targets including original documents Dthat tend to be erroneously detected as a multi-sheet feed such asenvelopes and folded paper will be described. It is assumed that, forexample, three original documents D have been mounted on the originalsupport 13, and in a single job, an operation for reading all (three)original documents D mounted on the original support 13 is performed.

When the power of the image reading apparatus 11 is turned on and thestart switch 22 is pressed, in the enabling mode that enables themulti-sheet feed detection, the computer 51 feeds and transports theoriginal documents D and instructs the reading section 40 to read theoriginal documents D.

Then, for example, if the second original document D is an envelope, themulti-sheet feed sensor 46 detects a multi-sheet feed, and interruptsthe job. That is, the computer 51 completes the reading operation of thefirst original document D, stops the transport of the second originaldocument D, and outputs the first data that is the data of the firstoriginal document D read in the reading operation performed before theinterruption. Then, the computer 51 displays a message that prompts theuser to reset the second and subsequent original documents D onto theoriginal support 13, and a message that prompts the user to set themulti-sheet feed detection mode on a display section (not illustrated)of the image reading apparatus 11 or the host device 53, or notifies thecontent by voice, or the like.

From the job interruption to the job restart, the disabling mode that isset in accordance with an instruction from the instruction section 20 ismaintained regardless of the detection results from the placement sensor45 and the transport sensor 47. The interrupted job is restarted inaccordance with a start instruction from the instruction section 20.

After the disabling mode is set and the start switch 22 is pressed, thecomputer 51 restarts the job in the disabling mode in which themulti-sheet feed detection is disabled according to the instruction fromthe instruction section 20, and performs the operation for reading thesecond and subsequent original documents D, which have been reset. Thatis, the interrupted job is restarted in accordance with the startinstruction from the instruction section 20. Then, the original documentD that was erroneously detected as a multi-sheet feed before theinterruption is transported and read in the state the multi-sheet feeddetection is disabled.

While the original document unit disabling mode is set in accordancewith an instruction from the instruction section 20, if the computer 51detects that the trailing edge of the second original document D haspassed through the multi-sheet feed sensor 46 based on a detectionsignal from the transport sensor 47, the computer 51 enables themulti-sheet feed detection by the multi-sheet feed sensor 46. That is,since the transport sensor 47 is disposed downstream of the multi-sheetfeed sensor 46 in the transport direction Y, the original document D hasalready passed through the multi-sheet feed sensor 46 when the originaldocument D passes through the transport sensor 47. Accordingly, thecomputer 51 switches to the enabling mode when the transport sensor 47is switched from on to off. When the job unit disabling mode or thedisable maintaining mode has been set, the set mode is maintained.

While the job unit disabling mode is set in accordance with aninstruction by the instruction section 20, when the last (for example,the third) original document D has passed through the transport sensor47 and the job is complete, the mode controller 64 enables themulti-sheet feed detection by the multi-sheet feed sensor 46. Then, theoutput controller 66 outputs the second data of the second and thirdoriginal documents D read in the reading operation performed after therestart as data that can be merged with the first data into a singlefile as a data stream. If the disable maintaining mode has been set, thecomputer 51 maintains the disabling mode until the power is switchedoff.

The host device 53 that has acquired the first data output from theimage reading apparatus 11 stands by until the second data is output.The second data is output from the image reading apparatus 11, and then,in the host device 53, the creation section 60 merges the first data andthe second data into a single

According to the above-described embodiment, the following advantagescan be achieved.

1. Time output controller 66 outputs the first data and the second dataas a data stream. Accordingly, the first data read before theinterruption, and the second data read after the restart, can be mergedinto a single file even if the job is interrupted by the multi-sheetfeed detection. Accordingly, the splitting of the read data into aplurality of files can be reduced when the original documents D to beread include the original documents D that tend to be erroneouslydetected as a multi-sheet feed.

2. For example, to read the original documents D that tend to beerroneously detected as a multi-sheet feed, the original document unitdisabling mode can be selected to disable the multi-sheet feed detectionby the multi-sheet feed sensor 46 until the original documents D havepassed through the multi-sheet feed sensor 46. After the passage of theoriginal documents D, the multi-sheet feed detection can be enabled.

3. In the job unit disabling mode, the multi-sheet feed detection can bedisabled until the job is complete. Accordingly, the job interruptiondue to erroneous detection can be reduced, for example, when theoriginal documents D that tend to be erroneously detected as amulti-sheet feed are included in the original documents D to be read ina single job. After the job is complete, the multi-sheet feed detectioncan be enabled.

4. From the job interruption to the job restart, when the originaldocuments D are reset, the placement sensor 45 and the transport sensor47 detect the resetting of the original documents D. However, from thejob interruption to the job restart, regardless of the detection resultsof the placement sensor 45 and the transport sensor 47, the disablingmode is maintained, and thereby the job can be restarted in thedisabling mode after resetting of the original documents D.

5. In the disable maintaining mode, in response to a disable instructionfrom the instruction section 20, the multi-sheet feed detection isdisabled until the power is switched off. Accordingly, the jobinterruption caused by erroneous detection can be reduced whenperforming a plurality of jobs including original documents D that tendto be erroneously detected as a multi-sheet feed.

6. The interrupted job can be restarted at any time by instructing theinstruction section 20 to issue an instruction to start the job. Theabove-described embodiment can be modified as described below.

In the above embodiment, the placement sensor 45 and the transportsensor 47 may be non-contact sensors, for example, photoelectronicsensors. In the above-described embodiment, the multi-sheet feed sensor46 may be a sensor that detects a multi-sheet feed based on thethickness of the original documents B.

In the above-described embodiment, the output controller 66 may outputthe first data and the second data after the job is complete. In theabove-described embodiment, the creation section 60 may be provided inthe image reading apparatus 11. That is, for example, the outputcontroller 66 may output the first data and the second data to thecreation section provided in the image reading apparatus 11, and theoutput section 56 may output the file created by the creation section tothe host device 53.

In the above-described embodiment, when the job is interrupted, thereading operation may be restarted by transporting the originaldocuments D that have been erroneously detected as a multi-sheet feed asit is without resetting the original documents D onto the originalsupport 13.

In the above-described embodiment, the next original document D may betransported before the reading operation of the preceding originaldocument D is complete. In the above-described embodiment, the patternof the notification section 27 may be changed for the individual modeselected from the disabling modes. For example, the notification section27 may light one of LEDs of different colors corresponding to theoriginal document unit disabling mode, the job unit disabling mode, andthe disable maintaining mode, respectively.

In the above-described embodiment, the start switch 22 for issuing a jobstart instruction may be omitted from the instruction section 20. Forexample, the computer 51 may start the job in accordance with a startinstruction input from the host device 53. Furthermore, the computer 51may restart the interrupted job in response to an instruction of thedisabling mode from the multi-sheet feed detection disabling switch 25.

In the above-described embodiment, in a case where the disablemaintaining mode is set, the disabling mode may be switched to theenabling mode and then the power of the image reading apparatus 11 maybe switched off in turning off (shutting off the power supply) the powerin accordance with an instruction from the power switch 21. Furthermore,in turning on the power of the image reading apparatus 11, the disablingmode may be switched to the enabling mode. Furthermore, the disablemaintaining mode may be continued after the power is turned off andfurther the power is turned on.

In the above-described embodiment, the disabling mode and the enablingmode may be switched in accordance with an instruction from theinstruction section 20. For example, the computer 51 may set thedisabling mode when the multi-sheet feed detection disabling switch 25is pressed once, and set the enabling mode when the multi-sheet feeddetection disabling switch 25 is pressed again. That is, it is notalways necessary that the disabling mode includes the original documentunit disabling mode, the job unit disabling mode, and the disablemaintaining mode. The disabling mode may include at least one of theoriginal document unit disabling mode, the job unit disabling mode, andthe disable maintaining mode.

In the above-described embodiment, the original support 13 and theplacement sensor 45 may be omitted. For example, a user may insert theoriginal documents D into the feed port 12A. Furthermore, a job may beended after the number of original documents D to be read in the job isinput via the instruction section 20 or the host device 53, and thereading operation of the original documents D of the specified number iscomplete. Furthermore, a job end may be instructed from the instructionsection 20 (for example, by pressing the stop switch 23, or the like bythe user).

In the above-described embodiment, while the job is interrupted, themulti-sheet feed detection modes may be changed in accordance with thedetection results of the placement sensor 45 and the transport sensor47. For example, based on the detection results of the placement sensor45 and the transport sensor 47, whether the original documents D, whichhave been detected as a multi-sheet feed, are reset onto the originalsupport 13 can be determined. Consequently, for example, after themulti-sheet feed sensor 46 detects a multi-sheet feed and the job isinterrupted, if the job is restarted without resetting the originaldocuments D onto the original support 13, the enabling mode may bechanged to the disabling mode (for example, the original document unitdisabling mode) and then the reading operation may be performed.

In the above-described embodiment, the transport sensor 47 may beomitted. For example, passage of the trailing edges of the originaldocuments D through the multi-sheet feed sensor 46 may be detected basedon the number of the original documents D fed and transported, or theread image data.

In the above-described embodiment, the instruction section 20 may be atouch panel. Furthermore, the multi-sheet feed detection disablingswitch 25 is not limited to the push switch, and alternatively, a leverswitch, a slide switch, or a mode switch may be employed.

The original documents may be any kind of original documents as long asthey can be fed and transported by the transport section 31, forexample, single sheets of paper, envelopes, cards, business cards,receipts, credit cards, insurance policies, or the like. The imagereading apparatus is not limited to the sheet-feed type image readingapparatus, and alternatively, may be a flat-bed type image readingapparatus having an automatic document feeding function (automaticdocument feeder) as an example transport section.

The entire disclosure of Japanese Patent Application No. 2015-213924,filed Oct. 30, 2015 is expressly incorporated by reference herein.

What is claimed is:
 1. An image reading apparatus comprising: atransport section including a roller configured to transport originaldocuments along a transport path; a reading section including a sensorconfigured to read images of the original documents transported by thetransport section; an output controller configured to output data of theoriginal documents read by the reading section; a multi-sheet feeddetection sensor configured to detect a multi-sheet feed of the originaldocuments transported by the transport section; an instruction sectionincluding a switch configured to issue an instruction to disablemulti-sheet feed detection by the multi-sheet feed detection sensor; anda transport detection sensor configured to detect the original documentstransported by the transport section, wherein, after a job forsequentially transporting a plurality of original documents to perform areading operation to read images is interrupted by multi-sheet feeddetection performed by the multi-sheet feed detection sensor, the outputcontroller determines whether a disabling mode in which the multi-sheetfeed detection is disabled in accordance with an instruction from theinstruction section has been set or not, when the disabling mode has notbeen set, the output controller stands by until the disabling mode isset, and when the job is restarted with the disabling mode having beenset, the output controller merges first data that is read in the readingoperation before the interruption and second data that is read in thereading operation after the restart into a single file and outputs thefile, the disabling mode includes an original document unit disablingmode for disabling the multi-sheet feed detection by the multi-sheetfeed detection sensor until the trailing edges of the original documentspass through the multi-sheet feed detection sensor, and if the originaldocument unit disabling mode is instructed by the instruction section,in response to detection of the passage of the trailing edges of theoriginal documents through the multi-sheet feed detection sensor basedon a detection signal detected by the transport detection sensor, themulti-sheet feed detection performed by the multi-sheet feed detectionsensor is enabled.
 2. The image reading apparatus according to claim 1,wherein the disabling mode includes a job unit disabling mode fordisabling the multi-sheet feed detection by the multi-sheet feeddetection sensor until the job is complete, wherein if the job unitdisabling mode is instructed by the instruction section, in response tothe job completion, the multi-sheet feed detection by the multi-sheetfeed detection sensor is enabled.
 3. The image reading apparatusaccording to claim 2, further comprising: a placement section on whichthe original documents to be read are mounted; and a placement detectionsensor configured to detect the original documents mounted on theplacement section; and, wherein athe transport detection sensor isfurther configured to detect the original documents mounted on theplacement section and transported by the transport section, whereinfromthe job interruption to the job restart, the disabling mode set inaccordance with the instruction from the instruction section ismaintained regardless of the detection results of the placementdetection sensor and the transport detection sensor.
 4. The imagereading apparatus according to claim 2, wherein the disabling modeincludes a disable maintaining mode for maintaining the state in whichthe multi-sheet feed detection by the multi-sheet feed detection sensoris disabled until the power supply is switched off.
 5. The image readingapparatus according to claim 2, wherein the instruction section issuesan instruction for starting the job, and the interrupted job isrestarted in accordance with the start instruction from the instructionsection.
 6. The image reading apparatus according to claim 1, furthercomprising: a placement section on which the original documents to beread are mounted; and a placement detection sensor configured to detectthe original documents mounted on the placement section, wherein thetransport detection sensor is further configured to detect the originaldocuments mounted on the placement section and transported by thetransport section, and from the job interruption to the job restart, thedisabling mode set in accordance with the instruction from theinstruction section is maintained regardless of the detection results ofthe placement detection sensor and the transport detection sensor. 7.The image reading apparatus according to claim 1, wherein the disablingmode includes a disable maintaining mode for maintaining the state inwhich the multi-sheet feed detection by the multi-sheet feed detectionsensor is disabled until the power supply is switched off.
 8. The imagereading apparatus according to claim 1, wherein the instruction sectionissues an instruction for starting the job, and the interrupted job isrestarted in accordance with the start instruction from the instructionsection.
 9. An image reading apparatus comprising: a transport sectionconfigured to transport original documents along a transport path; areading section configured to read images of the original documentstransported by the transport section; an output controller configured tooutput data of the original documents read by the reading section; amulti-sheet feed detection section configured to detect a multi-sheetfeed of the original documents transported by the transport section; aninstruction section configured to issue an instruction to disablemulti-sheet feed detection by the multi-sheet feed detection sectionbased on an operation of the instruction section by a user; and atransport detection section configured to detect the original documentstransported by the transport section, wherein, after a job forsequentially transporting a plurality of original documents to perform areading operation to read images is interrupted by multi-sheet feeddetection performed by the multi-sheet feed detection section, theoutput controller determines whether a disabling mode in which themulti-sheet feed detection is disabled in accordance with theinstruction from the instruction section has been set or not, when thedisabling mode has not been set, the output controller stands by untilthe disabling mode is set, and when the job is restarted with thedisabling mode having been set, the output controller outputs first datathat is read in the reading operation before the interruption and seconddata that is read in the reading operation after the restart such thatthe first data and the second data can be saved as a single file, thedisabling mode includes an original document unit disabling mode fordisabling the multi-sheet feed detection by the multi-sheet feeddetection section, the multi-sheet feed detection being configured todetect a multi-sheet feed of the original documents until the trailingedges pass through the multi-sheet feed detection section, and if theoriginal document unit disabling mode is instructed by the instructionsection, the multi-sheet feed detection performed by the multi-sheetfeed detection section is configured to change from being disabled tobeing enabled after detecting that the trailing edges of the originaldocuments pass through the multi-sheet feed detection section based on adetection signal detected by the transport detection section.
 10. Theimage reading apparatus according to claim 9, wherein the disabling modeincludes a disable maintaining mode for maintaining the state in whichthe multi-sheet feed detection by the multi-sheet feed detection sectionis disabled until the power supply is switched off.
 11. The imagereading apparatus according to claim 9, wherein the instruction sectionissues a start instruction for starting the job, and the interrupted jobis restarted in accordance with the start instruction from theinstruction section.
 12. The image reading apparatus according to claim9, wherein the disabling mode includes a job unit disabling mode fordisabling the multi-sheet feed detection by the multi-sheet feeddetection section until the job is complete, wherein if the job unitdisabling mode is instructed by the instruction section, in response tothe job completion, the multi-sheet feed detection by the multi-sheetfeed detection section is enabled.
 13. The image reading apparatusaccording to claim 9, further comprising: a placement section on whichthe original documents to be read are mounted; and a placement detectionsection configured to detect the original documents mounted on theplacement section, the transport detection section configured to detectthe original documents mounted on the placement section and transportedby the transport section, wherein from the job interruption to the jobrestart, the disabling mode set in accordance with the instruction fromthe instruction section is maintained regardless of the detectionresults of the placement detection section and the transport detectionsection.
 14. The image reading apparatus according to claim 9, furthercomprising a notification section configured to notify of a selectedmode, wherein, when the original document unit disabling mode isselected by the user, the output controller is configured to control thenotification section to notify that the original document unit disablingmode is being selected.
 15. A method of controlling an image readingapparatus comprising: transporting original documents along a transportpath; reading images of the transported original documents; outputtingdata of the original documents that have been read; detecting, by amulti-sheet feed detection section, a multi-sheet feed of the originaldocuments being transported; receiving an instruction to disable amulti-sheet feed detection by the multi-sheet feed detection section;detecting the original documents being transported; after a job forsequentially transporting a plurality of original documents to perform areading operation to read images is interrupted by multi-sheet feeddetection performed by the multi-sheet feed detection section,determining whether a disabling mode in which the multi-sheet feeddetection is disabled in accordance with the instruction from theinstruction section has been set or not; when the disabling mode has notbeen set, standing by until the disabling mode is set, and when the jobis restarted with the disabling mode having been set, outputting firstdata that is read in the reading operation before the interruption andsecond data that is read in the reading operation after the restart suchthat the first data and the second data can be saved as a single file,the disabling mode includes an original document unit disabling mode fordisabling the multi-sheet feed detection by the multi-sheet feeddetection section that detects a multi-sheet feed of the originaldocuments until the trailing edges pass through the multi-sheet feeddetection section, and if the original document unit disabling mode isinstructed by the instruction, allowing the multi-sheet feed detectionperformed by the multi-sheet feed detection section to be changed frombeing disabled to being enabled after detecting that the trailing edgesof the original documents pass through the multi-sheet feed detectionsection based on a detection signal of the original documents.
 16. Themethod of controlling an image reading apparatus according to claim 15,wherein the disabling mode includes a disable maintaining mode formaintaining the state in which the multi-sheet feed detection isdisabled until the power supply is switched off.
 17. The method ofcontrolling an image reading apparatus according to claim 15, whereinthe receiving of the instruction includes receiving a start instructionfor starting the job, and the interrupted job is restarted in accordancewith the start instruction.
 18. The method of controlling an imagereading apparatus according to claim 15, wherein the disabling modeincludes a job unit disabling mode for disabling the multi-sheet feeddetection by the multi-sheet feed detection section until the job iscomplete, wherein if the job unit disabling mode is instructed by theinstruction, in response to the job completion, the multi-sheet feeddetection by the multi-sheet feed detection section is enabled.
 19. Themethod of controlling an image reading apparatus according to claim 15,further comprising: detecting the original documents mounted on aplacement section, wherein from the job interruption to the job restart,the disabling mode set in accordance with the instruction is maintainedregardless of the detection result of the original documents beingplaced on the placement section and the detection result of the originaldocuments being transported.